you can plug 10amp plugs into a 15amp lead just not vise versa
so cheap way is just run a 15amp lead and a 4 plug power board for your needs
otherwise i would think you would need???
1x external 15amp power inlet $30-$50
1x external 10 amp power outlet $30-$50 (probably optional)
1 or more internal double pole outlet $30-$50
circuit breaker $90- $150
$100 in wire
and a sparky $$$ (will take a wild guess @ $300-$500)
im no electrician so i could be adding/ missing something here
but a rough idea on cost
Adam